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2 MW Design Draft — Self-Powered

Powered shell for high-density compute: on-site generation, battery storage, and direct-to-chip liquid cooling.

DRAFT · For discussion only

Grid available? See the Utility-Connected draft.

01 · Project Intent

A self-powered, liquid-cooled shell, ready for tenant fit-out

Deliver 2 MW of critical IT capacity (~2.2–2.4 MW total facility load) powered by on-site generation and battery storage. The core design is fully islanded, behind-the-meter: no utility connection required.

Speed to power

  • On-site natural-gas generation as primary source
  • No dependency on utility interconnection queues

High density

  • 80–120 kW per rack, ~17–25 racks
  • ~75% of heat captured to liquid

Repeatable

  • Modular 2 MW block, replicable on adjacent pads
  • Vendor-agnostic equipment specs
02 · Power Architecture

BESS + N+1 natural-gas gensets

Design load

  • 2.0 MW IT at target PUE ~1.10 (annual) to ~1.20 (peak)
  • Size generation and BESS to ~2.4 MW facility peak

N+1 gensets: charge BESS, support bus

  • N units carry ~2.4 MW facility load plus BESS recharge, with 10–15% headroom at site rating
  • Example basis (up to ~5,000–6,000 ft, 95–100°F): derate ~10–20%, site-dependent
  • Indicative: 4 × ~1.2 MW or 5 × ~1.0 MW nameplate

BESS (parallel, grid-forming)

  • Power: ~2.5–3 MW, full facility load
  • PCS stage also N+1, so a single inverter failure does not interrupt the critical load
  • Energy: ~8–12 MWh nameplate → ~4 h at ~2.2–2.4 MW, after depth-of-discharge and aging reserve
  • Inverter output continuously feeds critical buses A/B; covers genset trips, load steps, multi-hour backup

Gas supply

  • ~23–27 MMBtu/h at full output incl. BESS recharge (heat rate ~9–10 MMBtu/MWh)
  • ≈ 0.55–0.65 MMscf/day firm supply

Ranges are preliminary, pending load study, manufacturer site ratings, and gas supply assessment.

02a · Power One-Line

Islanded common-bus topology

MEDIUM-VOLTAGE COMMON BUSNG gensets · N+1 · charge BESS / support busG1G2G3G+1step-up xfmrsgen breakersBESSgrid-forming inverters · PCS N+1BESS xfmrBESS breakerBTM solaroptional=~inv.Paralleling switchgearsync, protection, load mgmtMV/LV AMV/LV BMV/LV MechBUS ABUS BMECH BUSIT loadD2C racks · dual-corded A+BCoolingCDUs · pumps · dry coolersControls & securitysmall UPS-backedSite controller + BESS SOC mgmtdispatch · load-follow · load sheddashed = control / comms · green = continuous BESS supplyCONTINUOUS CRITICAL PATHBESS inverter → buses A/B
Every source (N+1 gensets, BESS, optional solar) ties to one MV bus through its own breaker; separate A and B buses feed dual-corded IT loads. The grid-forming BESS continuously feeds critical buses A/B (green path); because it is on a parallel common bus, gensets can still carry the load if the BESS trips. Draft, not for construction.
02b · Operating Modes

Islanded operating modes

MODEBESS (GRID-FORMING)GENSETS (N+1)SOLAR (OPT.)WHAT HAPPENS1 · Normalforms & feeds buscharge BESS · supportoffsets fuelBESS inverter continuously feeds criticalbuses A/B; gensets recharge it and supportthe bus.2 · Genset tripfeeds bus · dischargingN−1 · spare startingas availableNo transfer needed: BESS keeps feeding theload until the spare unit syncs (minutes).3 · Planned maintenancefeeds bus · SOC heldN in serviceas availableOne unit out on N+1; redundancy covered byBESS for the battery's duration.4 · Gas curtailment/ full outagefeeds bus ~4 hoffas availableBESS carries the critical load multi-hour;staged load shed only at SOC floor.5 · Solar available (optional)feeds bus · chargingturned downonSolar charges the BESS and offsets fuel;gensets stay above minimum load.
Solid = active, dashed = off / standby. The BESS always forms and feeds the critical bus, so source events need no transfer at the load.
03 · Cooling

Direct-to-chip liquid cooling with dry coolers

Heat split (2 MW IT)

  • ~1.5 MW to liquid via cold plates + CDUs
  • ~0.5 MW residual air-side heat
  • Elevated-temperature D2C for near-zero water use

Facility water loop

  • Elevated temperature: ~45°C (113°F) supply / ~55°C return
  • Pure dry coolers as primary heat rejection; closed loop, propylene glycol for freeze protection
  • ~45°C supply holds a ~7°C approach even at 95–100°F design days

Water use

  • Near-zero water: no evaporative cooling in the base design
  • Adiabatic assist optional and minimal, only for the hottest design days at elevation

Air-side load

  • Rear-door HX / fan walls
  • Fed by a small closed-loop trim branch for cooler water (no water consumption)
  • Hot/cold aisle containment

Target PUE ~1.10–1.20 where practical, subject to final equipment selection and IT/CDU supply temperature limits.

03a · Cooling Loop

Cooling loop schematic

TECHNOLOGY COOLING LOOPFACILITY WARM-WATER LOOP (glycol)HEAT REJECTIOND2C cold platesCPUs / GPUs · ~75% of heatRack manifoldssupply / return per rackCDUs (N+1)liquid-to-liquid HXTCS return (hot)TCS supplyPumps N+1glycol facility loop~55°C returnDry coolers (N+1)PG glycol · freeze-protectedOptional adiabatic assisthottest design days only~45°C (113°F) supplyRear-door HX / fan walls~25% of heat (air side)Residual air heatmemory, PSUs, drivesSmall trim branchclosed loop · no water useair-side return tofacility loopFreeze protection~30–40% propylene glycolRed = return (hot) · blue = supply (cool) · dashed amber = optional / minimal. Pure dry cooling is the base design; temperatures indicative.
Closed glycol loops end to end. CDUs isolate the technology loop from the facility loop; pumps and dry coolers are N+1.
03b · Heat Split & Seasons

Heat split & seasonal operation

HEAT SPLIT · 2 MW ITLiquid (D2C) · ~75% · ~1.5 MWAir · ~25% · ~0.5 MWANNUAL OPERATION · EXAMPLE PROFILE: COLD WINTERS, HOT DRY SUMMERS · NEAR-ZERO WATERJFMAMJJASONDWinter (Nov–Mar)Pure dry cooling, fans modulated down;glycol + low-limit controls for freezeprotection; heat-recovery opportunity.Shoulder (Apr–May, Sep–Oct)Dry coolers only at ~45°C supply.Compressor-free, lowest PUE.Summer (Jun–Aug)Still pure dry cooling at ~45°C (113°F)supply through 95–100°F design days.Optional adiabatic assist only for rareextreme hours at elevation.Illustrative month bands; dry-only performance depends on site weather data and IT/CDU supply-temperature limits.
04 · Climate Fit

Cool, dry continental climates

Conditions

  • Example design basis: up to ~5,000–6,000 ft elevation
  • Cold winters, hot dry summers
  • Design dry-bulb up to ~95–100°F; low humidity

Cooling impact

  • ~45°C supply allows dry-only heat rejection year-round
  • Optional adiabatic assist reserved for extreme hours; low humidity makes it effective if ever used
  • Glycol and freeze protection for cold-weather operation

Altitude impact

  • Gensets derated for elevation and heat (site-dependent)
  • Thinner air reduces dry-cooler and fan capacity — size coils and fans accordingly
  • Electrical equipment altitude ratings verified
05 · Building Options

Building options & square footage

2 MW at 80–120 kW/rack ≈ 17–25 racks → ~1,500–4,000 sq ft of white space (incl. aisles and CDUs). The rest of the footprint is electrical, mechanical, and support space.

OptionDescriptionIndicative footprint
A · Pre-engineered metal buildingSingle-story shell, data hall + electrical/mechanical rooms~8,000–12,000 sq ft
B · Modular / prefabricatedFactory-built IT and power modules on prepared pad~5,000–8,000 sq ft of modules
C · Retrofit existing buildingAdapt existing industrial/warehouse structure~10,000–15,000 sq ft

Plus exterior yard for gensets, BESS (~8–12 MWh), transformers, and dry coolers (indicative 0.75–1.5 acres). All figures are draft ranges.

06 · Site Requirements

What a candidate site needs

Land

  • ~2–4 acres, flat, buildable
  • Industrial or compatible zoning

Gas supply

  • Firm ~0.55–0.65 MMscf/day at adequate pressure

Connectivity

  • Diverse fiber routes

Permitting

  • Air permit for prime generation (emissions controls may be required)
  • Noise limits at property line (gensets, dry coolers)
  • Fire code for BESS

Engineering studies

  • Grounding for islanded operation
  • Short-circuit & protection coordination with limited inverter fault current
07 · Next Steps

Next steps

1. Site screening

  • Shortlist sites against requirements

2. Feasibility

  • Gas supply, air permit, and load study

3. Basis of design

  • Lock power, cooling, and building option

4. Budget & schedule

  • Develop cost estimate and delivery timeline

Discuss a project →

This document is a design draft for discussion; all figures are preliminary. For sites with a viable grid connection, see the Utility-Connected draft.